Find P, Q, R and S in the given statements.
(i) Commas are inserted in a number after each 
.
(ii) Place value of a digit becomes 
times as it moves from ten's place to thousand's place.
(iii) There is no roman numeral to represent 
.
(iv) 100 + 100 + 100 in roman numerals is written as 
.
| P | Q | R | S | |
| A | Digit | 100 | 0 | CCC |
| B | Digit | 10 | 100 | XXX |
| C | Period | 1000 | 10 | MMM |
| D | Period | 100 | 0 | CCC |